1. Field of the Invention
The present invention involves electronic systems employing switching regulators and power supplies. More particularly, the present invention involves electronic systems for driving switching regulators that are employed in line noise-sensitive applications.
2. Discussion of the Related Art
Switching regulators and power supplies are commonly used in electronic systems, due to advantages such as low power dissipation, efficiency, and mass. Further, switching regulators and power supplies can provide stable voltages in the presence of a noisy line voltage.
A disadvantage of switching regulators is that they generate noise, both conducted and emitted, due to the physical switching operation itself, which is referred to as switching interference. Switching interference generally has a fundamental frequency component, which corresponds to the switching frequency of the switching regulator, and a plurality of harmonic components, which correspond to harmonics of the fundamental frequency component.
Many electronic systems, including avionics systems, employ multiple switching regulators, each of which may perform different functions (e.g., power regulation and power conversion) Each of these multiple switching regulators may have a different, corresponding switching frequency, depending on its function, the amount of power it must provide, its performance requirements, as well as other factors. Accordingly, each switching regulator may generate switching interference such that each has a distinct fundamental frequency component and a distinct spectrum of harmonic components. The switching interference generated by each switching regulator may be spectrally broad and unrelated to the switching interference generated by the other switching regulators.
Certain electronic devices and/or systems may have one or more spectral regions of interest where switching interference is particularly problematic. Examples include radio frequency (RF) receivers and driver circuitry for electro-optic devices, such as cameras or sensors. Accordingly, spectrally broad and unrelated switching interference may interfere with the function of such electronic devices and/or systems.
Related art solutions to switching interference include the use of filters and shielding. However, these solutions have undesirable consequences in that they increase the size, mass, and complexity of the electronic system in which they are deployed.
Accordingly, there is a need to control switching regulators that operate in a line noise-sensitive environments so that the noise is at least mitigated in the spectral regions of interest.